The North Atlantic-Eurasian Teleconnection associated with Summer Heatwaves in East Asia

Abstract:

Recently, as global warming is accelerated, extreme weather events occur more strongly and frequently. Summer heatwaves in East Asia have been stronger and more frequent in recent years, causing many socio-economic damages. The heatwaves on East Asia are caused by a combination of factors such as the extent of North Pacific High, Tibetan Anticyclone (or High), and the sea surface temperature (SST) over the Northwest Pacific with the Circum Global Teleconnection (CGT) pattern. The CGT pattern could be affected by the variability of SST in the Northwest Atlantic, but the mechanism behind it remains unclear. In this study, the heatwaves in East Asia was analyzed using the Maximum Temperature data of the last 41 years (1979 to 2019) provided by CRU. The ERA-interim reanalysis data was used to analyze the atmospheric circulation in the event of heatwaves in East Asia. Results show that anomalous high pressure located in the East Asian region is the most important condition for the heatwaves, connected to the CGT pattern in the upper atmosphere. The CGT patterns affecting the heatwaves in East Asia are related to the variability of Northwest Atlantic SST, indicating that heatwaves in East Asia are modulated by the variability of SST in the Northwest Atlantic in summer through the CGT pattern.

This work was funded by the Korea Meteorological Administration Research and Development Program under Grant KMI (KMI2018-03411) and the Korea Polar Research Institute (PE20090).